Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PKM Biochemistry > Diseases in Biochemistry > Flashcards

Diseases in Biochemistry Flashcards

1
Q

Mitochondrial disease characterized by bilateral loss of central vision due to neuroretinal degeneration. This is characterized by deficiency in which complex of the ETC?

A

Leber’s Hereditary Optic Neuropathy

Complex III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Inherited condition due to NADH:Q oxidoreductase (Complex I) deficiency. It is caused by a mutation in mitochondrial DNA and may be involved in Alzheimer’s disease and DM.

A

MELAS

Mitochondrial encephalopathy, lactic acidodis and stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Prion diseases are characterized by alteration of the conformation and physical properties of proteins endogenous to the human host. Normal PrP is a glycoprotein rich in ___ (secondary structure) while PrPsc has many ____.

A

PrP: alpha helices
PrPsc: beta sheets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Most fatal of the mitochondrial diseases characterized by deficiency in all complexes of the ETC

A

Fatal infantile mitochondrial myopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Mitochondrial disease characterized by deficiency in Complex II

A

Kearns-Sayre Syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Mitochondrial disease characterized by deficiency in Complex IV

A

Leigh’s Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Manifests as chronic hemolytic anemia, this condition is the most common enzyme defect in glycolysis.

A

Pyruvate kinase deficiency.

Aldolase A is another glycolytic enzyme that may be deficient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The exercise capacity of patients with ___ is low particularly if they are on high carbohydrate diets. By providing lipid as an alternative fuel (during starvation), when blood free fatty acid and ketone bodies are increased, work capacity is impoved.

A

Muscle phosphofructokinase deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Most common biochemical cause of congenital lactic acidosis. What is the pattern of inheritance?

A

Pyruvate dehydrogenase deficiency.
Because enzyme is deficient, pyruvate is shunted towards lactate production. Patients present with lactic acidosis and neurologic disturbance.

X-linked dominant!
There are only a few diseases that are X-linked dominant; another example is Alport Syndrome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Glycogen accumulation in liver and renal tubule cells; hypoglycemia; lactic acidemia; ketosis; hyperlipemia

Most likely diagnosis? Deficient enzyme?

A

Von Gierke’s Disease (Type I)

Glucose-6-phosphatase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Accumulation of glycogen in lysosomes.
Juvenile form: muscle hypotonia, death from heart failure by2.
Adult form: muscle dystrophy

A

Pompe’s Disease (Type II)
Lysosomal a1>4, a1>6 glucosidase
(Acid maltase)

MNEMONIC: Pompe’s affects the pump (heart).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Fasting hypoglycemia; hepatomegaly in infancy; accumulation of characteristic branched polysaccharide

A

Cori’s (or Forbe’s) Disease (Type III)
Debranching enzyme

MNEMONIC: ABCD
Andersen’s = Branching enzyme
Cori’s = Debranching enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Hepatosplenomegaly; accumulation of polysaccharide with few branch points. Death from heart or liver failure in first years of life

A

Andersen’s (Amylopectinosis) (Type IV)
Branching enzyme

MNEMONIC: ABCD
Andersen’s = Branching enzyme
Cori’s = Debranching enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Poor exercise tolerance. Muscle glycogen abnormally high. Blood lactate very low after exercise.

A

McArdle’s syndrome (Type V)
Muscle phosphorylase

McArdle's = Muscle phosphorylase
HEr's = HEpatic phosphorylase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hepatomegaly; accumulation of glycogen in liver; mild hypoglycemia; generally good prognosis

A

Her’s Disease (Type VI)
Liver phosphorylase

McArdle's = Muscle phosphorylase
HEr's = HEpatic phosphorylase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Poor exercise tolerance. Muscle glycogen abnormally high. Blood lactate very low after exercise. AND HEMOLYTIC ANEMIA

A

Tarui’s Disease

Muscle and erythrocyte phosphofructokinase I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Hepatomegaly; accumulation of glycogen in liver; mild hypoglycemia; generally good prognosis

A

Her’s Disease (Type VI)

Liver phosphorylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In the rare hereditary condition, considerable quantities of L-xylulose appear in the urine because of the absence of the enzyme necessary to reduce L-xylulose to xylitol.

A

Essential pentosuria.

Aminopyrine and antipyrine increase the excretion of L-xylulose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Benign and asymptomatic condition whose only symptom is the appearance of fructose in blood and urine. What is the enzyme deficiency?

A

Essential fructosuria;

hepatic fructokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Characterized by lack of hepatic fructokinase

A

Essential fructosuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Characterized by lack of aldolase B. Causes fructose-induced hypoglycemia because high levels of fructose-1-phosphate allosterically inhibit liver phosphorylase

A

Hereditary fructose intolerance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Autosomal recessive condition in which galactitol accumulates causing cataracts within a few days of birth; vomiting and diarrhea after milk ingestion; hepatosplenomegaly; and mental retardation. This condition is due to deficiency in ___.

A

Classic galactosemia

Galatose-1-phosphate uridyltransferase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

A benign condition characterized by galactosemia, galactosuria and an increased tendency for cataracts

A

Galactokinase deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

This condition is characterized by low levels of docosahexaenoic acid

A

Retinitis pigmentosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Inherited defect in fatty acid metabolism; affects only the liver; results in reduced fatty acid oxidation and ketogenesis, with hypoglycemia.

A

CPT-I deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Inherited defect in fatty acid metabolism; affects mainly the skeletal muscle; results in reduced fatty acid oxidation and ketogenesis, with hypoglycemia.

A

CPT-II deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Hypoglycemia occurs after eating the unripe fruit of the akee tree, which contains hypoglycin - an inactivator of medium and short chain acyl-CoA dehydrogenase

A

Jamaican vomiting sickness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Characterized by excretion of C6 - C10 dicarboxylic acids and by nonketotic hypoglycemia. What is the deficient enzyme?

A

Dicarboxylic aciduria

Medium chain acyl-CoA dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Neurologic disorder due to metabolic defect resulting in accumulation of phytanic acid found in dairy products and ruminant fat and meat.

A

Refsum’s disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Rare inherited absence of peroxisomes in all tissues. They accumulate C26 - C38 polyenoic acids in brain tissue; causing severe neurologic deficits.

A

Zellweger’s syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Deficiency in medium chain fatty-acyl dehydrogenase leads to fasting hypoglycemia. Pediatric patients are susceptible to this condition.

A

Sudden infant death syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Most common leukodystrophy. This is characterized by deficiency in which enzyme.

Symptoms include mental retardation, psychologic disturbances in adults. Demyelination.

A

Metachromatic leukodystrophy
Arylsulfatase A

MNEMONIC:
This condition is characterized by psychologic disturbances.
METAchromatic = ME TAMA sa ulo!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Name all glycogen storage disorders from Type I to Type VI

A

Viagra Pills Cause A Major Hard-on

I: Von Gierke
II: Pompe
III: Cori
IV: Andersen
V: McArdle's
VI: Her's
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Name all lysosomal storage disorders from Type I to Type VI

A

Viagra Pills Cause A Major Hard-on

I: Von Gierke
II: Pompe
III: Cori
IV: Andersen
V: McArdle's
VI: Her's
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

X-linked recessive disorder. Clinical symptoms include skin rash, kidney failure. Full symptoms are seen only in males.

A

Fabry’s disease.

MNEMONIC: FFAABBBRY
Foam cells found in glomeruli and tubules
Febrile episodes
Alpha galactosidase A deficiency
Angiokeratomas
Burning pain in extremities
BUN increased in serum
Boys
Renal failure
YX genotype (male, X linked recessive)

Also ZeBRa bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Mutation in sickle cell anemia

A

“HbS isn’t Very Good”
At sixth position of Hb beta chain, Valine is present instead of Glutamic acid.

SICKle cell = SIXth amino acid of Hb b chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Triad of skin rash, hoarseness, bone malformation. WHat is the deficient enzyme?

A

Farber’s Disease

Ceramidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Characterized by hepatosplenomegaly, erosion of long bones, mental retardation in infants.

A

Gaucher’s Disease

Deficiency in b-glucosidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Characterized by hepatosplenomegaly, erosion of long bones, mental retardation in infants.

A

Gaucher’s Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Characterized by mental retardation; myelin almost absent. Peripheral neuropathy, optic atrophy

A

Krabbe’s disease
Deficiency in b-galactosidase

“The Crab Nebula is a GALaxy”
Deficiency in galactocerebrosidase;
Has GLOBOID cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

This disease is caused by a deficiency in:

  1. b-glucosidase
  2. b-galactosidase
A
  1. Gaucher’s
  2. Krabbe’s

GaUchers: b-glUcosidase
KrAbbe’s: b-gAlactosidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

This condition is characterized by hepatosplenomegaly, mental retardation and is fatal in early life.

A

Niemann-Pick
Sphingomyelinase

MNEMONIC:
Niemann Picks his nose with his sFINGERS (sphingomyelinase).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Which sphingolipidoses are characterized by the presence of a cherry-red macula?

A

Tay-Sach’s

Niemann-Pick’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

In multiple sclerosis, there is loss both phospholipids and sphingolipids in the white matter. Which phospholipid in particular is lost in MS?

A

Ethanolamine plasmalogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

A deficiency in LDL receptor causes increased levels of LDL in the peripheral icrculation and an increased risk of atherosclerosis.

A

Familial hypercholesterolemia

Type II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Familial condition characterized by high VLDL and chylomicron, and low LDL and HDL. Patients are at increased risk for xanthomas and pancreatitis but with no increased risk for coronary atherosclerosis.

A

Familial lipoprotein lipase deficiency

Type I

47
Q

Familial condition characterized by high levels of VLDL and chylomicron remnants. Patients are at an increased risk for coronary heart disease. Which is deficient in this condition?

A

Familial dysbetalipoproteinemia
(Type III)

Deficient ApoE

48
Q

Familial condition characterized by increased VLDL production. Triad of CAD, DM type 2 and obesity

A

Familial hypertriglyceridemia

Type IV

49
Q

Condition is characterized by intestinal malabsorption with accumulation of lipids in intestine and liver. No chylomicron and VLDL found in blood stream.

A

Abetalipoproteinemia

Deficient apo B

50
Q

Characterized by deficiency in ABCA (ATP-binding casette transporter 1). Hallmark is hypertrophied orange tonsils

A

Tangier’s disease

MNEMONIC: Tangier’s = tangerine tonsils

51
Q

Characterized by deficiency in LCAT.

Causes corneal opacification with hepatosplenomegaly.

A

Fish eye disease

52
Q

Condition characterized by high HDL levels, associated with benefits to health and longevity

A

Familial hyperalphalipoproteinemia

53
Q

Condition characterized by decreased level or alteration in the structure of cardiolipin. Mitochondrial dysfunction causing heart failure and hypothyroidism

A

Barth syndrome

54
Q

In Alzheimer’s Disease, this protein undergoes a conformational transformation from being rich in alpha helices to a state rich in beta sheets. The latter is prone to self-aggregation. Which apolipoprotein has been implicated as a potential mediator of this transformation?

A

B-amyloid

Apolipoprotein E

55
Q

Patient presents with cyanosis, anxiety, headache and dyspnea. On extraction, blood was noted to be muddy brown in color. Diagnosis? Immediate treatment?

A

Methemoglobinemia
(Fe3+ in heme which does not bind O2 but binds CN-)

Mild: oral methylene blue or ascorbic acid
Severe: IV methylene blue

56
Q

Blood becomes “cherry pink” in color. Due to poisoning with an odorless gas; commonly seen in burn patients. Treatment?

A

Carbon monoxide poisoning
CO has 200x greater affinity.
Tx: Give 100% O2

57
Q

An intrinsic defect in RBC membrane that renders erythrocytes less deformable and vulnerable to splenic sequestration. Defect in which protein? Diagnostic test?

A

Hereditary spherocytosis.
Spectrin
Osmotic fragility test

58
Q

Patients homozygous for the trait present with mild hemolytic anemia. Hemoglobin variant has lysine at the 6th position instead of glutamate.

A

Hemoglobin C disease

59
Q

Anemia, accumulation of Hb Barts. Patients present only after 8 months of life.

A

Beta thalassemia

60
Q

Condition characterized by hyperextensible skin, tendency to bleed, hypermobile joints and increased risk of berry aneurysm.

A

Ehlers-Danlos syndrome

Collagen III

61
Q

Characterized by multiple fractures, blue sclerae, hearing loss and dental imperfections

A

Osteogenesis imperfecta

Collagen I

62
Q

Presents with glomerulonephritis (hematuria), end-stage renal disease, and hearing deficits

A

Alport’s syndrome

Collagen IV

63
Q

In this condition, skin easily breaks and blisters as a result of minor trauma. Conditon is due to mutations affecting ___.

A

Epidermolysis bullosa
(Collagen VII)
Collagen VII forms delicate fibrils that anchor basal lamina to collagen fibrils in the dermis.

64
Q

Patient all and thin, with dolichostenomelia, arachnodactyly, ascending aortic dilatation and dissection.

A

Marfan Syndrome

Fibrillin

65
Q

Genetic cause of emphysema

A

A1-antitrypsin deficiency

Inhibits elastase

66
Q

Impairment in human selenoprotein have been implicated in tumorigenesis and atherosclerosis; and are associated with this selenium deficiency cardiomyopathy

A

Keshan Disease

67
Q

Condition presents with lethargy, vomiting, hyperventilation, convulsions, cerebral edema, coma and death. May be treated with low protein diet

A

Hereditary hyperammonemia

Type I: carbamoyl phosphate synthetase I
Type II: ornithine transcarbamoylase

In Type II, mothers also exhibit hyperammonemia and an aversion to high CHON diet.

68
Q

Patient presents with hyperornithinemia, hyperammonemia, and homocitrullinuria. What is the underlying genetic defect?

A

HHH Syndrome
Due to defect in ornithine transporter (transports ornithine from cytosol to mitochondria)

Homocitrullinuria develops because transcarbamoylase (in the absence of ornithine), works with lysine to form homocitrulline.

69
Q

Friable, tufted hair (trichorrhexis nodosa) associated with elevated levels of arginosuccinate in CSF, blood and urine. What is the deficient enzyme? Diagnostic test?

A

Arginosuccinase deficiency.

Measurement of erythrocyte arginosuccinase activity on umbilical cord blood

70
Q

1 - 2 g of citrulline daily is excreted in this disorder of urea metabolism.

A

Arginosuccinate synthetase deficiency

71
Q

An autosomal recessive condition characterized by hyperargininemia. This condition does not present until patient has reached age 2 to 4 years.

A

Arginase deficiency

72
Q

Due to a deficiency in alpha-ketoacid decarboxylase. Causes severe CNS defects, mental retardation and death. Causes increased alpha keto acids in the blood, esp leucine

A

Maple syrup urine disease

73
Q

Condition characterized by urolithiasis, nephrocalcinosis and early mortality from renal failure or hypertension. If this was due to a defect in amino acid catabolism, what is the condition and which amino acid is involved?

A

Primary hyperoxaluria

Defect is failure to catabolize glyoxylate which is oxidized to oxalate (increases stone formation).
Glyoxylate is a product of deamination of GLYCINE.

74
Q

Increased tendency to form stones due to defective reabsorption of a group of amino acids. What is the treatment?

A

Cystinuria
No transporter for COAL
Cystine, Ornithine, Arginine, Lysine

Treat with acetazolamide to alkalinize the urine!

75
Q

Deficiency in tyrosine aminotransferase leads to tyrosinemia

A

Richner-Hanhart Syndrome

Type II tyrosinemia

76
Q

In this condition, the urine darkens on exposure to air. Later in the natural history of the disease, there is arthritis and connective tissue pigmentation. What is the condition? Enzyme defect? Pathophysiology of symptoms?

A

Alkaptonuria due to deficiency in homogentisate oxidase.

Homogentisate is a product of tyrosine catabolism. Oxidation of homogentisate in the urine leads to darkening. Oxidation of homogentisate to benzoquinone acetate poiymerizes and binds to connective tissue, leading to arthritis and pigmentation (ochronosis).

77
Q

Pellagra like signs and symptoms are seen due to impaired intestinal and renal transport of an amino acid.

A

Hartnup Disease
Due to impaired transport of Tryptophan and neutral amino acids.

Remember that Tryptophan is required for niacin synthesis

78
Q

Condition characterized by mental retardation, growth retardation, fair skin, eczema and musty body odor

A

Phenylketonuria
Due to deficiency in Phenylalanine Hydroxylase

PHenylketonuria = Phenylalanine Hydroxylase

79
Q

Lack of melanin increases the risk of skin Ca. This condition can result from a lack of migration of neural crest cells.

A

Albinism

Deficiency in Tyrosinase

80
Q

This condition can cause mental retardation, osteoporosis, tall stature, kyphosis, lens subluxation, and atherosclerosis.

A

Homocystinuria due to:

  1. Cystathionine synthase deficiency (with B6, converts homocysteine to cystathionine and then cysteine).
  2. Low affinity for cystathionine synthase
  3. Homocysteine methyltransferase deficiency
    (Converts homocysteine to methionine)
81
Q

Porphyria which presents as decreased red cell counts and hemoglobin

A

X-linked sideroblastic anemia

ALA synthase deficiency

82
Q

Photosensitivity or chronic inflammation to overt blistering and shearing in sun-exposed areas; abdominal pain and neuropsychiatric symptoms.

The most common form is due to which enzyme deficiency.

A

Porphyria cutanea tarda

Deficiency in uroporphyrinogen decarboxylase

83
Q

Presents with abdominal pain and neuropsychiatric symptoms. Urinary delta-aminolevulinic acid is elevated.

A

ALA dehydratase deficiency

84
Q

Most porphyrias are autosomal dominant except ____ which is characterized by deficiency in ___. Does NOT exhibit photosensitivity.

A

Congenital erythropoietic purpura
(Autosomal recessive)
Uroporphyrinogen III synthase

85
Q

Presents with headache, memory loss, peripheral neuropathy, nausea, abdominal pain, diarrhea. CBC demonstrates coarse, basophilic stippling of RBC

A

Lead poisoning

86
Q

Most common cause of unconjugated hyperbilirubinemia

A

Neonatal (physiologic) jaundice

87
Q

Rare autosomal recessive disorder characterized by severe congenital jaundice. Mutations in the gene encoding bilirubin-UGT is characteristic. Disease is often fatal within the first 15 months.

A

Type I Criggler-Najjar

Type 2 is less severe; and can respond to large doses of Pb

88
Q

Unconjugated hyperbilirubinemia more common in males and entirely harmless

A

Gilbert Syndrome

89
Q

Benign autosomal recessive disorder consisting of conjugated hyperbilirubinemia. Centrilobular hepatocytes contain an abnormal black pigment derived from epinephrine.

A

Dubin-Johnson Syndrome

Mutation in MRP-2

90
Q

Rare benign conjugated hyperbilirubinemia. Liver histology is normal. Precise cause unknown

A

Rotor Syndrome

91
Q

Severe burning and aching of the feet, hyperesthesia, and vasomotor changes of the feet that leads to excessive sweating

A

Burning feet syndrome aka

Grierson-Gopalan syndrome

92
Q

Megaloblastic anemia with degeneration of the spinal cord

A 
Pernicious anemia
(Vitamin B12 deficiency)
93
Q

Clinical manifestations include headache, nauseam ataxia related to increased CSF; hepatomegaly; thickening of long bones and hypercalcemia; and excessive dryness and desquamation of the skin.

A

Vitamin A toxicity

94
Q

Most important preventable cause of blindness

A

Vitamin A deficiency

95
Q

Cheilosis, desquamation, inflammation of the tongue and a seborrheic dermatitis

A

Riboflavin deficiency

96
Q

Photosensitive dermatitis, dementia, diarrhea

A

Pellagra

B3/niacin deficiency

97
Q

Triad of hyperuricemia, mental retardation and self-mutilation. Which two metabolites accumulate in this condition?

A

Lesch-Nyhan Syndrome
HGPRT deficiency

Lesch Nyhan = He’s Got Purine Recovery Trouble
PRPP and uric acid

98
Q

How does Von Gierke’s syndrome cause hyperuricemia?

A

Von Gierke’s syndrome is characterized by deficiency in glucose-6-phosphatase which turns G6P (obtained from glycogenolysis) into free glucose. In this syndrome, accumulation of G6P leads to shunting of some G6P into the pentose phosphate pathway, increasing ribose-5-phosphate, and subsequent purine metabolism. Elevated purines eventually are catabolized into uric acid.

99
Q

Immunodeficiency in which both T cell and B cells are sparse and dysfunctional.

A

Adenosine deaminase deficiency
ADA converts adenosine to inosine. With deficiency, adenosine builds up, converted to AMP and dATP which inhibits ribonucleotide reductase.

100
Q

Severe liver damage leads to hypouricemia and increased excretion of hypoxanthine and xanthine. Patients are at an increased risk of xanthine lithiasis.

A

Xanthine oxidase deficiency

101
Q

Abnormal growth, megaloblastic anemia and excretion of large amounts of orotate in urine

A

Orotic aciduria

Due to low activities:
A. Orotidine phosphate decarboxylase
B. Orotate phosphoribosyltransferase

102
Q

Match condition with characteristic defect in DNA repair.

  1. Xeroderma pigmentosum
  2. Hereditary nonpolyposis Ca

A. Mismatch repair
B. Base excision repair
C. Nucleotide excision repair
D. Double-strand break repair

A
  1. C

2. A

103
Q

Marked sensititivity to sunlight and subsequent formation of multiple skin Ca and premature death

A

Xeroderma pigmentosum
Autosomal recessive
Defect in nucleotide excision repair

104
Q

Autosomal recessive disorder resulting in development of cerebellar ataxia and lymphoreticular neoplasms. Defect in?

A

Ataxia telangiectasia

ATM (ataxia telangiectasia mutated) and ATR proteins normally sense DNA damage and phosphorylate (and activate) p53

105
Q

A congenital disorder of glycosylation. Absence of Golgi-located GDP-fucose transporter leads to absence of fucosylated ligands for selectins. Patients prone to life-threatening, recurrent bacterial infections and psychomotor and mental retardation. What is the tx?

A

Leukoacyte adhesion deficiency (II)

Tx: oral fucose

106
Q

Acquired mild anemia characterized by the presence of Hg in urine due to hemolysis of red cells, particularly during sleep. The basic defect in this condition is somatic mutation in this gene. Which 2 proteins are deficient?

A 
Paroxysmal nocturnal hemoglobinuria
PIG-A (Phosphatidylinositol glycan class A)

Proteins anchored by GPI missing:
Decay accelerating factor
CD59

107
Q

In PNH, what 2 proteins are missing? What is their normal function?

A

Decay accelerating factor
CD59

Interact with components of the complement system to prevent hemolytic action.

At night, drop in pH increases susceptibility to lysis by the complement system.

108
Q

These conditions are a result of defects in synthesis of glycans in alpha-dystroglycan, which results in defective interaction with laminin-2 (merosin) in basement membrane.

A

Congenital muscular dystrophies

Walker-Warburg; Muscle-eye-brain disease, Fukuyama

109
Q

This uncommon disease presents with progressive psychomotor retardation and a variety of physical signs. It is characterized by mutant GlcNAc phosphotransferases. Lack of GlcNAc 1-phosphate on mannose residues on many enzymes lead to secretion of these enzymes rather than being targeted to lysosomes.

A

I-Cell Disease

110
Q

Developmental disorder affecting connective tissue and CNS. Increased risk of supravalvular aortic stenosis.

A

Williams syndrome

Absence of elastin

111
Q

Characterized by increased bone density and in one form, RTA and cerebral calcification. Enzyme deficiency?

A

Osteopetrosis
Carbonic anhydrase II
in Chromosome 8 (HARD BONE = 8 letters)

Osteoclasts secrete H+ into environment to increase solubility of hydroxyapatite. Within the cell, OH left is neutralized by H+ formed by normal carbonic anhydrase. In deficiency, osteoclast function is impaired.

112
Q

Short limbs, normal trunk size, macrocephaly and skeletal abnormalities. Pattern of inheritance? Mutations in gene encoding ___?

A

AchonDroplasia
Autosomal Dominant
Fibroblast growth factor receptor 3 (FGFR3)
(A tyrosine kinase receptor)
Mutation involved substitution of Arg for Gly

113
Q

Mutation in genes leading to formation of abnormal Type II collagen, manifests as degeneration of joint cartilage and vitreous body of the eye.

A

Stickler Syndrome

PKM Biochemistry (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions